In modern telecommunications, there is a common use of amplifiers to amplify signals which are transmitted over a communication network. With telecommunication being more and more accessible and common, there is a need to improve the quality and efficiency of the amplifiers which are used to amplify signals for telecommunication purposes.
As modulated signals which are common for wireless communications such as CDMA-2000, WCDMA and LTE generally have a high peak-to-average power ratio (PAPR) which in turn has demanded a different type of amplifiers to operate efficiently.
To operate with these types of modulated signals, the power amplifiers have to be very linear in order to prevent in-band distortion and out-of-band emission. As such, one option to achieve this is to operate the amplifier at a large back-off region far from saturation. However, this inevitably leads to low efficiency as well as a higher than normal power consumption of the amplifier. Various other options are available to improve the efficiency in operating the power amplifiers, but whilst these have solved one problem, they have, by their presence, introduced other inefficiency issues on operating the amplifiers.